STARK LOCALIZATION AND MIXING PHENOMENA BETWEEN DIFFERENT STARK-LADDERS IN COUPLED QUANTUM-WELLS

Abstract

We have studied Stark localization of the minibands in coupled quantum wells by considering the effect of an external electric field, applied along the growth axis, on a multiple-quantum well system which is identical to the effect of the ladder-like increment in the potential energy. The mixing feature of the Stark ladders is explained by using an analysis of the spatial probability distribution of the carrier. We have found that at intermediate ladder values a certain degree of delocalization of the carrier wave functions exists and finally at large ladder values the Stark-ladder stales become localized within individual wells and a combined band structure occurs. (C) 1995 Academic Press Limited